const path = require('path');
//根据不同的文件名后缀 填写合适的Content-Type
module.exports = (filePath)=>{
    //.pop 取最后一个点后的内容
    let ext = path.extname(filePath).split('.').pop().toLowerCase();
    if (!ext) {
        ext = filePath;
    }
    return mimeTypes[ext]||mimeTypes['txt'];
};

const mimeTypes = {
    '323':    'text/h323',
    'acx':    'application/internet-property-stream',
    'ai': 'application/postscript',
    'aif':    'audio/x-aiff',
    'aifc':   'audio/x-aiff',
    'aiff':   'audio/x-aiff',
    'asf':    'video/x-ms-asf',
    'asr':    'video/x-ms-asf',
    'asx':    'video/x-ms-asf',
    'au': 'audio/basic',
    'avi':    'video/x-msvideo',
    'axs':    'application/olescript',
    'bas':    'text/plain',
    'bcpio':  'application/x-bcpio',
    'bin':    'application/octet-stream',
    'bmp':    'image/bmp',
    'c':  'text/plain',
    'cat':    'application/vnd.ms-pkiseccat',
    'cdf':    'application/x-cdf',
    'cer':    'application/x-x509-ca-cert',
    'class':  'application/octet-stream',
    'clp':    'application/x-msclip',
    'cmx':    'image/x-cmx',
    'cod':    'image/cis-cod',
    'cpio':   'application/x-cpio',
    'crd':    'application/x-mscardfile',
    'crl':    'application/pkix-crl',
    'crt':    'application/x-x509-ca-cert',
    'csh':    'application/x-csh',
    'css':    'text/css',
    'dcr':    'application/x-director',
    'der':    'application/x-x509-ca-cert',
    'dir':    'application/x-director',
    'dll':    'application/x-msdownload',
    'dms':    'application/octet-stream',
    'doc':    'application/msword',
    'dot':    'application/msword',
    'dvi':    'application/x-dvi',
    'dxr':    'application/x-director',
    'eps':    'application/postscript',
    'etx':    'text/x-setext',
    'evy':    'application/envoy',
    'exe':    'application/octet-stream',
    'fif':    'application/fractals',
    'flr':    'x-world/x-vrml',
    'gif':    'image/gif',
    'gtar':   'application/x-gtar',
    'gz': 'application/x-gzip',
    'h':  'text/plain',
    'hdf':    'application/x-hdf',
    'hlp':    'application/winhlp',
    'hqx':    'application/mac-binhex40',
    'hta':    'application/hta',
    'htc':    'text/x-component',
    'htm':    'text/html',
    'html':   'text/html',
    'htt':    'text/webviewhtml',
    'ico':    'image/x-icon',
    'ief':    'image/ief',
    'iii':    'application/x-iphone',
    'ins':    'application/x-internet-signup',
    'isp':    'application/x-internet-signup',
    'jfif':   'image/pipeg',
    'jpe':    'image/jpeg',
    'jpeg':   'image/jpeg',
    'jpg':    'image/jpeg',
    'js': 'application/x-javascript',
    'latex':  'application/x-latex',
    'lha':    'application/octet-stream',
    'lsf':    'video/x-la-asf',
    'lsx':    'video/x-la-asf',
    'lzh':    'application/octet-stream',
    'm13':    'application/x-msmediaview',
    'm14':    'application/x-msmediaview',
    'm3u':    'audio/x-mpegurl',
    'man':    'application/x-troff-man',
    'mdb':    'application/x-msaccess',
    'me': 'application/x-troff-me',
    'mht':    'message/rfc822',
    'mhtml':  'message/rfc822',
    'mid':    'audio/mid',
    'mny':    'application/x-msmoney',
    'mov':    'video/quicktime',
    'movie':  'video/x-sgi-movie',
    'mp2':    'video/mpeg',
    'mp3':    'audio/mpeg',
    'mpa':    'video/mpeg',
    'mpe':    'video/mpeg',
    'mpeg':   'video/mpeg',
    'mpg':    'video/mpeg',
    'mpp':    'application/vnd.ms-project',
    'mpv2':   'video/mpeg',
    'ms': 'application/x-troff-ms',
    'mvb':    'application/x-msmediaview',
    'nws':    'message/rfc822',
    'oda':    'application/oda',
    'p10':    'application/pkcs10',
    'p12':    'application/x-pkcs12',
    'p7b':    'application/x-pkcs7-certificates',
    'p7c':    'application/x-pkcs7-mime',
    'p7m':    'application/x-pkcs7-mime',
    'p7r':    'application/x-pkcs7-certreqresp',
    'p7s':    'application/x-pkcs7-signature',
    'pbm':    'image/x-portable-bitmap',
    'pdf':    'application/pdf',
    'pfx':    'application/x-pkcs12',
    'pgm':    'image/x-portable-graymap',
    'pko':    'application/ynd.ms-pkipko',
    'pma':    'application/x-perfmon',
    'pmc':    'application/x-perfmon',
    'pml':    'application/x-perfmon',
    'pmr':    'application/x-perfmon',
    'pmw':    'application/x-perfmon',
    'pnm':    'image/x-portable-anymap',
    'pot,':   'application/vnd.ms-powerpoint',
    'ppm':    'image/x-portable-pixmap',
    'pps':    'application/vnd.ms-powerpoint',
    'ppt':    'application/vnd.ms-powerpoint',
    'prf':    'application/pics-rules',
    'ps': 'application/postscript',
    'pub':    'application/x-mspublisher',
    'qt': 'video/quicktime',
    'ra': 'audio/x-pn-realaudio',
    'ram':    'audio/x-pn-realaudio',
    'ras':    'image/x-cmu-raster',
    'rgb':    'image/x-rgb',
    'rmi':    'audio/mid',
    'roff':   'application/x-troff',
    'rtf':    'application/rtf',
    'rtx':    'text/richtext',
    'scd':    'application/x-msschedule',
    'sct':    'text/scriptlet',
    'setpay': 'application/set-payment-initiation',
    'setreg': 'application/set-registration-initiation',
    'sh': 'application/x-sh',
    'shar':   'application/x-shar',
    'sit':    'application/x-stuffit',
    'snd':    'audio/basic',
    'spc':    'application/x-pkcs7-certificates',
    'spl':    'application/futuresplash',
    'src':    'application/x-wais-source',
    'sst':    'application/vnd.ms-pkicertstore',
    'stl':    'application/vnd.ms-pkistl',
    'stm':    'text/html',
    'svg':    'image/svg+xml',
    'sv4cpio':    'application/x-sv4cpio',
    'sv4crc': 'application/x-sv4crc',
    'swf':    'application/x-shockwave-flash',
    't':  'application/x-troff',
    'tar':    'application/x-tar',
    'tcl':    'application/x-tcl',
    'tex':    'application/x-tex',
    'texi':   'application/x-texinfo',
    'texinfo':    'application/x-texinfo',
    'tgz':    'application/x-compressed',
    'tif':    'image/tiff',
    'tiff':   'image/tiff',
    'tr': 'application/x-troff',
    'trm':    'application/x-msterminal',
    'tsv':    'text/tab-separated-values',
    'txt':    'text/plain;charset=utf8',
    'uls':    'text/iuls',
    'ustar':  'application/x-ustar',
    'vcf':    'text/x-vcard',
    'vrml':   'x-world/x-vrml',
    'wav':    'audio/x-wav',
    'wcm':    'application/vnd.ms-works',
    'wdb':    'application/vnd.ms-works',
    'wks':    'application/vnd.ms-works',
    'wmf':    'application/x-msmetafile',
    'wps':    'application/vnd.ms-works',
    'wri':    'application/x-mswrite',
    'wrl':    'x-world/x-vrml',
    'wrz':    'x-world/x-vrml',
    'xaf':    'x-world/x-vrml',
    'xbm':    'image/x-xbitmap',
    'xla':    'application/vnd.ms-excel',
    'xlc':    'application/vnd.ms-excel',
    'xlm':    'application/vnd.ms-excel',
    'xls':    'application/vnd.ms-excel',
    'xlt':    'application/vnd.ms-excel',
    'xlw':    'application/vnd.ms-excel',
    'xof':    'x-world/x-vrml',
    'xpm':    'image/x-xpixmap',
    'xwd':    'image/x-xwindowdump',
    'z':  'application/x-compress',
    'zip':    'application/zip'
};

